Photo of the Day: Mission San Xavier del Bac in Tucson, Ariz.

The Pima Air & Space Museum in Tucson, Ariz., is one of the great aviation museums in the country.

Though it might seem difficult to believe, in less than 150 years, this arid area known as “The Valley of the Sun” has grown from small farming community to major metropolitan city.

The National Park Service will reopen the Grand Canyon to tourists for Memorial Day weekend but there will be additional restrictions in place, and many popular viewing locations will likely remain closed, officials said.